Note: Descriptions are shown in the official language in which they were submitted.
~3~
FLICKER FLAME FIRE
The present lnvention relates to a display unit ~or
simulating a solid-fuel fire, particularly but not solely for
use with a gas or electric heater.
One form of conventional gas or electric heater presently
on the market has a unit for simulating a solid-fuel fire in
order to enhance the appeal to customers. This unit haq a
fibre-glass cover shaped and coloured to represent a pile of
coals or logs, under which cover are located at least one
filament lamp and rotatable apertured disc. Heat rising from
the illuminated lamp causes the disc to rotate, whereupon it
casts moving patterns of shadows and light onto the inner
surface of the cover. Parts of the cover are coloured to
transmit orange-yellow light and hence simulate glowing solid
fuel, whereas the remainder of the cover substantially prevents
light transmission and hence retains its original colouring
(thereby simulating solid fuel which is not yet alight). A
ma~or disadvantage of this type of simulation unit is that,
becau~e the rotation of the disc i~q substantially uniform, the
variation of illumination is regular, re~ulting in an
unrealistic and unsatisfactory illuqion detrimental to the
overall appearance of the heater.
U.S. Patent No.4253045 discloses various proposals to vary,
apparently in random manner, the illumination cast onto the
inner surface of a simulation unit cover, in an attempt to
imitate realistically the glowing effect of a sol-ld fuel fire.
~n object of the present invention is to provide a display
~3~
: 2
unit which can simulate realistically a solid-fuel fire at a
modest cost and in a simple and reliable manner.
The present invention provides a display unit for
simulating a solid-~uel fire, the unit comprising a housing
having a surface which simulates solid-fuel, at least one gas
discharge lamp withln the housing, the at least one lamp having
electrodes shaped and arranged to provide, in use, an unstable
mode discharge, at least one window in the simulation surface to
. _
enable the lamp to be viewed directly ~rom out~ide the housing.
The direct viewing of the lamp(s) in unstable mode
discharge may be by line-of-sight, whether solely through air or
through air and a trartsparent material; additionally the direct
viewing may include reflection. In al~ cases, the source
itself of the randomly moving light must be visible to an
observer.
Preferably a substantially transparent section o~ tkte
simulation sur~ace forms a window. Additionally or
alternatively, an apertt~tre in the simulation surface forms a
window.
Two or more of the lamps may be mounted on a common support
secured to the housing, thereby ensuring that the lamps are
rigidly held in the housing. In an alternative form, a lamp is
secured individually to the simulation sur~ace, for example by a
member which is embedded within that surface. In either
arrangement a lamp can be installed or replaced easily and
quickly.
: 3
The display unit of the pre~ent invention may be used
either alone, merely for decorative purposes, or in combination
with a heater fuelled, for example, by gas or electricity.
The display unit of the present invention provides
simulation of a solid-fuel fire in which the fla~es themselves
can be seen, rather than the prior art units described above
which only attempt to imitate the glow of a solid-fuel fire
and/or the indirect light from flickering flames. The unit of
present invention affords a direct view of imitation flickering
flames, who~e movement is achieved electrically rather than by,
for example, mechanical means; moreover, the unit of the present
invention does not utilize any gas burners to produce gas
- flames, although of cour~e the unit coul~ be used in a heater
which i~ fuelled by ga~.
15 - In order that the invention may more clearly be understood,
a description is now given, by way of example only, reference
being made to the sole accompanying Figure of a heater with a
display unit embodyin~ the present invention.
In the Figure, a heater 1 with a conventional arrangement
of gas burner ~ets 2 and radiant elements 3 incorporate~ a
display unit L~ to simulate a coal fire. The Figure shows a
heater 1 with the front of unit 4 cut away in order that the
interior can be seen.
Display unit ll has a grey translucent top cover 5 whlch
~5 ~imulates a bed of coal~ and of embers; the cover 5 has six
non uniformly spaced holes, over each of which there sits a
separate hollow black element 6 to simulate an individual piece
of coal. Thus the cover 5 and elements 6 together form a
simulation surface. Each element 6 has at least one
substantially transparent section forming a window 7 through
which can be seen a flicker-~lame lamp 8 positiomed within the
element 6 near to the window(s) 7; All the lamps 8 are
mounted, via standard bayonet holder~ 99 on a common support
plate 10 which i5 fixed to khe housing of heater 1.
The fllcker-flame la ps are of a conYentional type in which
a glass enclosure containing neon has two flame-shaped
electrodes, the size of the cathode and the spacing of the
electrodes encouraging the discharge to wander over the
electrode surfaces in a random manner. This type o~ lamp has
been known widely for many years (see for ç~ample British Patent
Specification ~o.997961 which was published on 14 July, 1965),
but there has been no prior disclosure or use of such lamps in a
unit according to the present invention as claimed, even though
there has been much interest and activity ln the industry
concerning the development of improved and more realistic
simulated solid-fuel fires.
The display unit 4 also has two filament bulbs 11 (only one
being in view in the Flgure), above each o~ which there is a
spir~er 12 with apertureq 13 in order to cast patterns of light
and shadow on the inner surface of cover 5. Located along the
back of unit 4 and above part of the spinners 12 is a strip of
frosted glass 1l~ which contributes to the random scattering of
light from bulbs 11.
When the display unit is operatlng, the randomly moving
"~ .
~23~5
: 5
discharge o~ lamps 8 can readily been seen through the
respective window(s) 7 to give the appearance of real ~lickerlng
flames, while the fluctuating light produced by bulbs 11,
spinners 12 and frosted glasa 14 is transmitted through cover 5
to give the appearance of a varying glow. Clearly display
unit 14 can be operating whether or not the heater 1 is
producing any heat; thus the unit 4 in heater 1 can be used to
produce an aesthetically and pleasing display, enhancing the
appearance of a room, even when it is not necessary (and indeed
may be undesirable, at that time) for the room to be heated.
The unit 4 also has a control whereby the bulb~ 11 can be
switched between an 'off' mode and two different light output
settings, so that the overall appearance of the unit can be
varied as desired.
-- The houaing of heater 1 has a heat insulating barrier 15
which separates the section incorporating the radiants 3 from
the display unit 4, becau~e undue heating of lamps 8 and bulbs
11 can adversely affect their operation and longevity.
Additionally there may be ducta and/or ~ fan in the heater in
order to promote air circulation around unit 4 in order to
minimiae the effect on the lamps 8 of heat from radiant~ 2. In
a modified heater, unit 4 is located below the radiants.
The artificial coal piecea 6 are made by forming a
tranaparent plastica material moulding, fixing a mask to the
moulding and then applying ~for example by spraying) appropriate
colouring, so that when the mask is removed the portions
remaining transparent form the ~lndow(s) 7. The cover also, if
: '.
des~red, can be manufactured in the ~ame way.
A display unit embodying the present invention may include
any one or more of the following modification~ from the ~orm
qhown in the sole Figure. The support plate may be arcuate
such that the lamps 8 are not in the same horizontal plane,
and/or it may be twiqted about an axis parallel to its
longitudinal d$mension such that the lamps 8 have different
orientations; additionally or alternatively the support bar may
be positioned within the unit in such a way that the lamps 8 do
not lie in a single horizontal straight line substantially
parallel to the back surface of the unit 4. The surface
simulating a solid-fuel fire may have at least one aperture
through which a flicker-flame lamp can be viewed directly,
whereby the at least one aperture comprises a window; the
apertured surface may be manufactured solely by moulding, or the
surface may be manufactured initially without these apertures
(e.g. by moulding) and the apertures are cut out subsequèntly.
One or more of the lamps 8 may be individually fixed solely to
the simulation surface itself in order to improve the randomness
of the po~itioning of the lamps over the surface; thus, for
example, a qinsle lamp may be secured to two wires each with one
end embedded in the surface.
The unit may have a dimming control whereby the power input
to, and hence the light output of, the lamps 8 can be ad~usted
a~ required. The lamps in the unit may be eleotrically
conneoted in a series arrangement or in a parallel arrangement,
or in a combination of each ($n the latter ca~e the variation in
,
: 7
electrical potential drop acro~ diPferent lamps resulting in a
variation in light output and rate of discharge movement between
different lamps). One or more of the lamps may have a sleeve
to promote scattering of light; the sleeve may include a
reflective portion to direct additional light forwards. The
cover 5 and elements 6 may be modified such that they form a
surface simulating a wood fire, with or without coal in it.
The gas burners and radiants may be replaced by some form of
electrically powered heating unit, for e~ample electrical
radiant heater elements; alternatively the display unit may be
used by itself, i.e. without any form of heating unit, for
decorative purposes alone.
Clearly, a display unit embodying the.present invention may
have as many flicker-flame lamps as considered approriate, there
^being no technical limitation or optimum amount; however it
should be noted that if a unit is to have only a few such lamps,
it is ad~antageous for one or more to have a plurality of
corresponding windows in order to maximise the ef~ect of the
lamps.
A unit embodying the present invention may also include
other features, not disclosed above, which would be evident to a
man skilled in the art.
